Apparatus for signaling the location of recesses in a flow conductor



ay 7, i968 Filed Oct. 2l, 1965 N` F. BROWN APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR l2 Sheets-Sheet l f Novvncm E Bvovvn ATTORNEYS May 7, w58 N. F. BRQWN APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR l2 Sheets-Sheet 2 Filed Oct. 2l, 1965 n S mw n m0 1 NA Er W, O WB n M A O dq.

May 7, E968 N. F. BROWN APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR Filed OC.. 2l, 1965 12 SheetS-Shet 3 INVENTOR Norman F. Br own gf/W myx. V/ZZQQ// May 7, g68 N F, BROWN 3,381,750

APPARATUS FOR slONALlNG THB LOCATION OF RECESSES IN A FLOW CONDUCTOR Filed OCT.. 2l, 1955 l2 ShGSS-Shet 4 ANN Illl

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OF RECESSES IN A FLOW CONDUCTOR l2 Sheets-Sheet 5 Filed Oct. 2l, 1965 R W mm x m .mo \m `@vr f .n :l WB MA e El. 3 v n v Q m No w 3 o 3 l2 Sheets-Sheet 6 Q R N m .w m w 6 m. a W.. m DOH 8 a. a. 65 lo 5 B 8 m.. w 3 W 6M I0 W 0| 6 Q. u. W 5 aq 2 7s a 1.. Cl o0 8 9 N 555 GIO 8| I A 1 5&6 M l l l l a n II nl.. Dn l l l I I l I I l l l l l l I l |1| .r l All IIII Il.. O N

May 7, 1968 N. F, BROWN APPARATUS FOR SIGNALING THE LOCATION 0F RECESSES IN A FLow CONDUCTOR Filed Oct. 2l, 1965 N. F. BROWN APPARATUS FOR SIGNALING THE LOCATION May 7, 1968 OF RECESSES IN A FLOW CONDUCTOR 12 Sheets-Sheet 'i Filed Oct. 21, 1965 5&5

51a F IG r 2O ANNIE# INVENTOR NORMAN E BROWN ATTORNEYS FlGrZZ May 7, 1958 N. F. BROWN 3,381,750

APPARATUS FOR SIGNALING THE LOCATION OF REcEssEs I'N A mow CONDUCTOR Filed Oct. 21, 1965 l2 Sheets-Sheet 8 INVENTOR l 556 r NORMAN F. BROWN Fla-23 WW1/WW ATTORNEYS May 7, 1968 N. F. BROWN 3,381,750

APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR Filed Oct. 2l, 1965 l2 Sheets-Sheet 9 V aas 8a /asr s 32 i 7 33| 33 INVENTOR NORMAN F. BROWN A m W7 BY Wfrf ATTORNEYS May 7, 1968 N. F, BROWN APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR l2 Sheets-Sheet 10 Filed Oct. 2l, 1965 FIG .-32

FIG-53 INVENTOR NORMAN E BROWN mwa?, BY

ATTORNEYSl May 7, 1968 N. F. BROWN 3,38750 APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR 12 Sheets-Sheet ll Filed Oct. 2l, 1965 95s@ ssa 954@ INVENTOR NORMAN E' BROWN fw@- BY i ay 7, 1968v N. F. BROWN 3,381,750

APPARATUS FOR SIGNALING THE LOCATION OF RECESSES IN A FLOW CONDUCTOR Filed OCT,- 21, 1965 12 Sheets-Sheet 1:14v

INVENTOR NORMAN F. BROWN ATTORNEYS United States Patent O 3,381,750 APPARATUS FOR SIGNALING THE LGCATION F RECESSES IN A FLOW CONDUCTOR Norman F. Brown, Dallas, Tex., assigner to Utis Engineering Corporation, Dallas, Tex., a corporation of Delaware Filed Oct. 21, 1965, Ser. No. 499,358 23 Claims. (Cl. 166-64) ABSTRACT 0F THE DISCLQSURE A signaling device movable through a flow conductor tor signaling the position of recesses therein yand having laterally outwardly expandable sensor members movable on the mandrel between inner retracted positions and outer expanded positions, latch means engageable with the sensor means to prevent movement of the sensor means from expanded to retracted position until a predetermined movement of the mandrel relative to the sensor means has taken place to move the latch means out of latching position to permit the sensor means to move to retracted position. The mandrel is yieldably held against longitudinal movement relative to the sensor means to create a pressure signal indicating the engagement of the sensors of the device with the recess in the conductor. The device is designed for operation in either longitudinal direction, and for selectively rendering the device operative during movement in only one or the other of such longitudinal directions, if desired.

This invention relates to signaling devices and more particularly to a device for indicating the location thereof in a iiow conductor during the movement of the signaling device through the ilow conductor.

An object of this invention is to provide a new and improved signaling device, which may be connected to any suitable tool movable through a :dow conductor, which requires an increase in the force moving the signaling device and the tool through the ow conductor when the signaling device moves past predetermined locations in the flow conductor to indicate such locations of the tool.

Still another object is to provide a signaling device which is movable through a ow conductor provided with longitudinally spaced internal annular recesses and having means engageable with the shoulders defining the recesses to increase the resistance to the movement of the signaling device through the ilow conductor each time the signaling device moves past such recesses.

Still another object is to provide a signaling device which will operate properly when moved in either longitudinal direction through the flow conductor to provide a signal each time the signaling device moves past internal obstructions of the iiow conductor located at known predetermined locations.

A further object is to provide a signaling device, connectable to a tool movable by liquid under pressure introduced into the dow conductor which produces shock and pressure waves in the liquid upstream thereof each time the signaling device moves past predetermined loc-ations of the flow conductor.

Still a further object is to provide a signaling device having laterally outwardly expandable means which are movable into internal annular recesses of the ow conductor and having releasable latch means engageable with the expandable means to hold the expandable means in expanded positions.

Another object is to provide a signaling device Wherein the latch means is moved to inoperative position to Cil 3,38L Patented May 7, 1968 permit movement of the expandable means back to their retracted positions to permit movement of the signaling device through the flow conductor by a force greater than that needed to move the signaling device through the ilow conductor when the latch means is in inoperative position and the expandable means are not in their expanded positions.

Still another object is to provide a signaling device having a manderl provided with a sensor means movable laterally on the mandrel between inner retracted positions and outer expanded positions, a latch means engageable with, the sensor means to prevent movement of the sensor means from its expanded to its retracted position until the mandrel and latch means move a predetermined distance relative to the expanded sensor means to permit its movement to its retracted position, and means for yieldably resisting such movement of the mandrel and the latch means relative to the sensor means.

Still another object is to provide a signaling device wherein the means for yieldably resisting the movement of the mandrel and latch means relative to the sensor means comprises spring means.

Still another object is to provide a signaling device wherein the means for yieldably resisting such movement of the mandrel and the latch means relative to the sensor means comprises a hydraulic assembly.

A further object is to provide a signaling device having sensor means mounted on a mandrel which are movable laterally outwardly to expanded position to engage an internal obstruction of a flow conductor during the passage of the signaling device through the flow conductor, means for yieldably resisting the movement of the mandrel relative to the sensor means when the movement of the sensor means has been arrested, and means associated with the mandrel and the sensor means for holding the sensor means in its expanded position until the mandrel has moved a predetermined dist-ance relative to the sensor means against the resistance of the resisting means.

A still further object is to provide a signaling device of the type described which has trigger means operatively associated with the resisting means and the sensor means which frees the mandrel from the resisting means to permit the movement of the mandrel relative to the sensor means after the mandrel has moved a predetermined distance relative to the sensor means.

Another object is to provide Aa signaling device having adjustable control means for selectively rendering the signaling device operative during its movement in one or the other longitudinal direction through a ow conductor and inoperative during its movement therethrough in the opposite longitudinal direction.

Additional objects and advantages of the invention will be readily apparent from the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

FIGURE 1 is a vertical view with some parts broken away and some parts in section, of a signaling device embodying the invention showing the sensor members thereof in their inner retracted positions during the movement of the signaling device through a flow conductor;

FIGURE 2 is a view similar to FIGURE 1 showing the sensor members in their expanded positions and extending into an internal annular recess of the tlow conductor;

FIGURE 3 is a side view of the signaling device;

FIGURE 4 is a perspective exploded View of the sensor members and the latch means of the signaling device illustrated in FIGURES l, 2 and 3;

FIGURE 5 is a sectional view taken on line 5 5 of FIGURE 4;

FIGURE 6 is a perspective view of the mandrel of the signaling device;

FIGURE 7 is a schematic illustration of a well installation showing the signaling device connected to a train of well tools being pumped downwardly through the tubing of the well;

FIGURE 8 is a vertical sectional view, with some parts removed, of a signaling device embodying the invention and having a hydraulic assembly for yieldably resisting the movement of the latch means from its latching operative position to its inoperative position;

FIGURE 9 is a vertical partly sectional view, with some parts broken away, of another signaling device embodying the invention;

FIGURE l is a vertical sectional view of a signaling device illustrated in FIGURE 9 showing the sensor members thereof in their inner retracted positions during the downward movement of the signaling device through a flow conductor;

FIGURE 11 is a view similar to FIGURE l0 showing the sensor members of the signaling device in their expanded positions and extending into an internal annular recess of the ow conductor;

FIGURE l2 is a sectional view taken on line 12-12 of FIGURE 9;

FIGURE 13 is an exploded perspective view of the sensor members and latch means of the signaling device illustratcd in FIGURES 9, l0, l1 and l2;

FIGURE 14 is a perspective view of a spring retainer block of the signaling device illustrated in FIGURES 9, 10, 1l and 12;

FIGURE l is a vertical partly sectional View of a signaling device embodying the invention;

FIGURE 16 is a vertical sectional view, with some parts removed and some parts broken away, of the signaling device illustrated in FIGURE l5;

FIGURE 17 is a sectional view taken on line 17-7 of FIGURE FIGURE 18 is a sectional view taken on line 18-1S of FIGURE 16;

FIGURE 19 is a sectional view taken on line 19-19 of FIGURE 15;

FIGURE 2O is a sectional view taken on line 20-20 of FIGURE 15;

FIGURE 21 is a sectional View taken on line 21-21 of FIGURE 16;

FIGURE 22 is an exploded perspective view of a cage of the signaling device illustrated in FIGURES 15 through 21;

FIGURE 23 is an exploded perspective view of a mandrel and sensor members of the signaling device illustrated in FIGURE 15;

FIGURE 24 is a fragmentary perspective view of a control rod of the signaling device illustrated in FIG- URE 15;

FIGURE 25 is a perspective view of a trigger link of the signaling device illustrated in FIGURE 15;

FIGURE 26 is a perspective view of a latch housing of the signaling device illustrated in FIGURE 15;

FIGURE 27 is a perspective view of a control sleeve of the signaling device illustrated in FIGURE 15;

FIGURE 28 is a perspective view of a modified form of the control sleeve useable in the signaling device illustrated in FIGURE l5;

FIGURE 29 is a vertical partly sectional view, with some parts broken away, of the upper portion of a moditied form of the signaling device embodying the invention;

FIGURE 30 is a view similar to FIGURE 29, being a continuation thereof, and showing the lower portion of the signaling device;

FIGURE 3l is a sectional view taken on line 31-31 of FIGURE 29;

FIGURE 32 is a sectional View taken on line 32-32 of FIGURE 30;

FIGURE 33 is a sectional view taken on line 33-33 of FIGURE 30;

FIGURE 34 is a vertical partly sectional view with some parts broken away and some parts removed of the signaling device illustrated in FIGURES 29 and 30;

FIGURE 35 is a sectional view taken on line 35-35 of FIGURE 34;

FIGURE 36 is a sectional view taken on line 36--36 of FIGURE 34;

FIGURE 37 is an exploded perspective view of a mandrel and sensor members of the signaling device illustrated in FIGURES 29 and 30;

FIGURE 38 is an exploded perspective view of a trigger link of the singnaling device illustrated in FIG- URES 29 and 30;

FIGURE 39 is a perspective view of a control sleeve assembly of the signaling device illustrated in FIGURES 29 and 30;

FIGURE 40 is a fragmentary perspective view of the control rod illustrated in FIGURES 29 and 30; and,

FIGURE 4l is a vertical fragmentary partly sectional view of a modied form of the spring assembly of the signaling device illustrated in FIGURES 29 and 30.

Referring now particularly to FIGURES l through 7 of the drawings, the signaling device 20 embodying the invention includes a central tubular mandrel 21 having a ball connector 22 secured to one end thereof and a socket connector 23 secured to the other end thereof. The ball connector has an inner reduced threaded portion or pin 25 which is threaded in one end portion of the tubular mandrel, an etxernal annular tiange 26 intermediate its ends which provides an inwardly facing annular shoulder or surface 27 which limits inward movement of the ball connector relative to the mandrel, a neck portion 28 and a ball 29.

The socket connector 23 has a lirst section 32 whose inner threaded portion or pin 33 is threaded in the opposite end of the mandrel, an external ange 34 intermediate its ends which provides an inner shoulder 35 which limits movement of the rst section into the mandrel, and an outer externally threaded portion 38 which is threaded in the second section 40 of the socket connector. The socket connector sections 32 and 4t) have spaced facing annular arcuate seat surfaces 41 and 42, respectively, between which a ball of a ball connector, such as the ball 29 of a ball connector 22, may be positioned for limited universal rotation therebetween. The neck of such ball connector will then extend outwardly through the passage or aperture 45 of the socket section 40.

A protector sleeve disposed about the mandrel has two sections 51 and 52. The rst sleeve section 51 extends between an external ange 53 of the mandrel and the external ange 34 of the first socket section 32. The inner edge portions of the rst sleeve section are received in the recesses 54 of the mandrel ange. The outer end of the rst sleeve section has an internal annular ange 55 which abuts the shoulder 35 of the flange 34 to limit outward longitudinal movement of the first sleeve section.

The second sleeve section 52 is disposed between the ange 26 of the ball connector 22 and the mandrel flange 53, its inner edges being received in the recesses 61 of the mandrel ange and its outer end being provided with an annular internal ange 64 which abuts the shoulder 27 of the ball connector ange 26 to limit outward longitudinal movement of the second sleeve section.

Each of the protector sleeve sections has cricurn-ferentially spaced pairs of long and short slots 65 and 66, respectively. The short slots of each sleeve section are aligned with the long slots of the other sleeve section. The four pairs of aligned short and long slots are also aligned with the longitudinal recesses 67 of the mandrel flange to provide two pairs of windows 68 and 68a.

The windows 68 extend longitudinally inwardly from near the outer end of the sleeve section 52 and past the mandrel flange in one longitudinal direction and the windows 68a extend longitudinally 'inwardly in the opposite direction from near the outer end of the sleeve section 51 and past the mandrel flange.

A pair of sensor or feeler members 70 extend outwardly through the windows 68. The inner ends of the sensor members are biased outwardly by a pair of flat springs 71 which extend longitudinally outwardly between the mand-rel and the flange 54 of the sleeve section 53 and have laterally outwardly extending end portions 72 which are received in the recesses 73 of the sleeve section 53. The inner ends of the springs are received in the internal longitudinal extending recesses 74 of the sensor members. The sensor members are biased in one longitudinal direction by springs 77 Whose inner ends bear against the external annular shoulders 78 of a pair of plungers 79 and whose lower ends bear against the surfaces 81 defining the ends of the recesses 82 provided in opposite end portions of a cross pin 84. The cross pin extends transversely through aligned elongate slots of the two sensor members and the aligned slots S6 of the mandrel. The upper ends of the plungers are provided with angular recesses 87 in which are received the angular portions of the keys defining the upper ends of the slots S5.

The inner ends of the sensor members 70 have external bosses 90 which provide inwardly divergent oppositely facing shoulders 91 and 92. The shoulders 91 extend at a smaller angle relative to the longitudinal axis of the signal device than the shoulders 92. The bosses are receivable in the internal annular recesses 9S of the locating nipples 99 connected at desired spaced locations in the string of tubing 160. The upper and lower annular shoulders or surfaces 96 and 97 of the locating nipple dening the top and bottom sides of the annular recess 9S may extend perpendicularly relative to the longitudinal axis ot' the locating nipple.

A second cross pin 84a extends laterally through the longitudinal slots 85a of the sensor keys 70a and the aligned slots 86a of the mandrel and the two cross pins are biased longitudinally away from one another by a pair of springs and 111 which are disposed in the mandrel. One end of the outer spring 110 extends about the longitudinal guide extension 112 of the cross pin 84 and bears against its shoulder 113 and the other end of the outer spring extends about the similar guide extension 112a of the cross pin 84a and bears against its shoulder 113a. Opposite end portions of the inner spring 111 similarly extend about the guide extensions 114 and 114g and bear against the shoulders 115 and 115a of the cross pins 84 and 84a, respectively.

A pair of latch sleeves 116 and 116:1 slidably mounted on the mandrel on the opposite sides or" its flange 53 are biased toward one another and toward the oppositely facing shoulders 118 and i18n of the flange by a pair of springs 119 which extend through diametrically opposite slots 120 of the flange. One hooked end of each spring 119 extends about a pin 122 rigidly secured to a pair of radially extending lugs 124 of the latch sleeve 116 and its other hooked end extends about a similar pin 12251 carried by the lugs 124a of the other latch sleeve 11611.

The latch sleeve 116 has a pair of radially outwardly extending latch bosses which, when the sensor members 70 are in the longitudinal positions on the mandrel illustrated in FIGURE 1, extend into the slots 131 of the sensor members and their upper surfaces or shoulders 134 engage the shoulders 135 defining the longitudinally inner ends of the slots 131. The engagement of the shoulders 134 and 135 holds the latch sleeve 116 in the longitudinally outward position illustrated in FIGURE 1 against the biasing force of the springs 119.

When the sensor members 70 move laterally outwardly to their outer or expanded positions illustrated in FIG- URE 2, the latch sleeve 116 is moved inwardly by the force of the springs 119 until its movement is arrested by the engagement of its inner annular end surface with CII 6 the shoulder 118 of the mandrel flange. At this time the outer surfaces of the latch bosses 130 abut the inner surfaces 141 of the sensor members 170 and lock the sensor members against direct return toward their retracted positions.

The beveled longitudinally outer cam shoulders 142 of the latch bosses are engageable with the similarly beveled shoulders 143 of the sensor members when the sensor members are moved longitudinally outwardly on the mandrel as will be explained below.

The latch sleeve 116:1 has opposed slots 144 in which inner portions of the sensor members 79 are received when the sensor members 70 are in their inner retracted positions illustrated in FIGURE 1. The sensor members 76 are also provided with internal recesses 145 in alignment with the mandrel flange and in which the latch bosses 130 are receivable. This permits the sensor members to move to their retracted or inner positions when the latch sleeve 116 is in its longitudinally outer position and also when it is in the innermost position abutting the mandrel flange shoulder 118.

The sensor members 70a and their latch sleeve 116:1 and their associated elements are identical in structure to the sensor members 70, the latch sleeve 1160 and their cooperating elements, and, accordingly, the sensor members 70a, the latch sleeve 116a and their cooperating elements have been provided with the same reference numerals, to which the subscript a has been added as the corresponding elements of the sensor members 70, the latch sleeve 116 and their cooperating elements.

Referring now particularly to FIGURE 7 of the drawing, the locating device may be employed to position any suitable well tool T at a specic location in a string of well tubing 100 some of whose sections are connected by the usual coupling collars and others of which are connected at predetermined known locations by the locating nipples 99. The well has a packer Q which closes the annulus A between the casing C and the tubing. The tubing has a valve section S having one or more lateral ports O above the packer Q which are openable by a valve sleeve V slidable in the valve section. The well has the usual casing head H provided with a pipe or conduit 161, having a valve 162 connected therein by means of which, when the valve is open, fluid under pressure may be exhausted from the annulus. A pipe 164 conducting fluid, preferably an incompressible liquid, from a pump P, has two branches; one, controlled by valve 165, connected to the casing annulus and the other, controlled by valve 174, connecting to the tubing string 100. The tubing string 100 also has a vent pipe 160 closable by a suitable valve 167. A pressure sensing and recording device 168 of any suitable well known type senses and records the pressure and shock waves in the pipe 164 downstream of the pump P and therefore of the liquid operating the signaling device 20. The well also has the usual lubricator connected to the usual valves 181 and 182.

The signaling device 20 is connected to a string or train of tools, such as the two or more sealing well tools 171 and 172 which sealingly engage the internal surfaces of the tubing. The signaling device is connected to the uppermost of the sealing well tools 171 by its ball connection 22. The two sealing wel-l tools are also pivotally connected by a suitable lball and socket connection 173 which spaces the two sealing well tools from one another so that at least one of the sealing well tools is always in sealing engagement with the tubing, the connecting neck of the balll and socket connection ybeing long enough to cause the two sealing well tools to span any coupling collar recess, locating nipple 99 or other internal recess in the string of tubing. The tool T is connected to the lowermost sealing `well tool 172 by a suitable connecting means. The ibosses 90 of the sensors are considerably longer than any internal recess of the string of tubing other than the recesses 95 of the locating nipples 99.

After closing valve 182 and opening the valve 181, the

tool T is inserted in the lubricator 180, followed by sealing well tools 171 and 172 and the signaling device 20. These four components are connected together by universal joints thus forming a tool string capable of passing through pipe bent to a radius as short as 60 inches. The two sealing well tools are preferably located in the lubricator below the level of pipe connections 164 and 166. Valves 181, 165 and 167 are then closed, valves 174, 182 and 162 are opened, and liquid is pumped into the tubing by the pump P. The valve V being in its upper position fluid in the tubing string below the train of tools may iiow into the casing annulus through the ports O and from the annulus through the pipe 161 since the valve 162 is now open. The sensor members 70 and 70a are now held in their inner retracted positions by the engagement of their bosses 90 and 99a with the internal surfaces of the tubing, as shown in FIGURE 1, and, since their bosses are of considerably greater length than any internal recesses of the string of tubing other than the recesses 95 of the locating nipples, the sensor members can move outwardly to their expanded positions only when their bosses move into alignment with a recess 95 of a locating nipple. When this assembly of well tools passes through the uppermost locating nipple 99 connected in the string of tubing and the bosses of the sensor members of the signaling device move into alignment with the latching recess of the uppermost locating nipple, the sensor members 70 and 70a are moved laterally outwardly by their springs 71 and 71a to the positions illustrated in FIGURE 2. This outward movement of the sensor members 70 and '70a moves their shoulders 135 and 135:1 out of engagement with the shoulders 134 and 134e of the latch lugs 130 and 130a of the latch sleeves 116 and 116a, respectively, and the two latch sleeves are moved inwardly by the springs 119 until their inner edges abut the opposite shoulders 118 and 118e of the mandrel ange.

As the downward movement of the signaling device continues, the cam shoulders 92 of the sensor members 7 0 and the cam shoulders 91a of the sensor members 70a contact the lower annular shoulder 97 of the locating nipple and, since the latch lugs 130 now prevent inward movement of the sensor members, the sensor members cannot now move further downwardly. The cross pin 84 is now also held against downward movement since it now engages the shoulders 17 defining the lower ends of the slots 85 of the sensor members 70.

The mandrel, the latch sleeves and the upper cross pin 84a are now moved downwardly relative -to the sensor members 70 and 70a and to the cross pin 84 against the biasing force exerted by the springs 110 and 111 between the cross pins and against the resistance of the springs 77a of the sensor members 70a. This increased resistance to the movement of the assembly of well tools now offered by the signaling device causes a pressure or shock wave to be generated in the liquid being pumped into the string of tubing which is sensed and recorded by the pressure sensing and recording device 168. Such increase in pressure in the liquid being pumped now causes downward movement of the mandrel, the latch sleeves and of the upper cross piece 84a while the sensor members and the bottom cross pin 84 are held against downward movement until the latch sleeves 116 and 116a move downwardly relative to the sensor members 7G and '70a to positions wherein their latch lugs are out of engagement with the shoulders 141 and 141a of the sensor members 70 and 70a thus releasing the sensor members for inward movement.

The camming engagement between the shoulders 92 of the sensor members 70 and the shouder 97 of the locating mandrel now causes the sensor members 70 to pivot inwardly above the shoulders 134 of the latch lugs 13() and the camming engagement of their shoulders 135 with the shoulders 134 moves the latch sleeve 116 downwardly on the mandrel. As soon as the shoulders 92 of the sensor members 70 move out of engagement with the shoulder 97 of the locating nipple, the springs 110 and 111 move the cross pin 84 downwardly on the mandrel until the cross pin 84 again engages the top surface of the inner portion 25 of the ball connector member 22. The engagement of the bottom surface of the cross pin with the surfaces 171 of the sensor members 70 dening the bottom ends of their slots causes simultaneous downward movement of the sensor members 70 with the cross pin 84. The sensor members 70 and the latch sleeve 116 are then again in the positions relative to the mandrel illustrated in 4FIGURE 1.

When the mandrel andthe latch sleeve 116a have moved downwardly relative to the sensor members 70a to the positions wherein the latch bosses 136a are out of engagement with the shoulders or surfaces 141a, the sensor members 70a are pivoted inwardly when their cam shoulders 91a engage the nipple shoulder 97 so that the shoulders 142e of the latch bosses move into engagement with the shoulders 143a of the sensor members 76a. The sensor members 70a -will then remain in such upper positions relative to the mandrel and the latch, sleeve 116a during the continued downward movement o the signaling device through the string of tubing. rlhe latch bosses will now be lodged in the recesses 145a of the sensor members 70a.

Such pivotal movement of the two pairs of sensor members occurs substantially simultaneously as the train of well tools continues to be moved downwardly through the tubing to the desired location and the signaling device successively passes through the longitudinally spaced locating nipples connected in the tubing. The sensor members move outwardly each time their bosses move into alignment with a latch recess of a locating nipple and cause a shock or pressure wave to travel through the liquid being pumped into the upper end of the tubing when the downward movement of the sensor members 70 is arrested due to their engagement with the lower shoulder 97 of such locating nipple. The pressure sensing and recording device will therefore precisely indicate the location of the train of well tools until the tool T has been located at a desired location in the well tubing.

If it is thereafter desired to move the train of tools upwardly to a higher location in the tubing, the valves 174 and 162 are closed and the valves 165 and 167 are opened. If the pressure of the well is now sutciently great, it may move the train of tools upwardly. If it is not sufficiently great liquid may be pumped into the annulus A through the pipe 164 and the open valve 165. The liquid pumped into the annulus A passes through the open ports O into the tubing below the train of well tools and moves it upwardly. As the signaling device moves into the lowermost locating nipple it encounters during such upward movement, the sensor members 70 and 70a move outwardly into its latch recess 95 and the upward movement of the sensor members is momentarily arrested when the shoulders 91 of the sensor members 70 and the shoulders 92a of the sensor members 70a engage the upper shoulder 96 of such locating nipple. At this time the upper cross pin 84a engages the shoulders 171a defining the upper ends of the slots 85a of the sensor members 70a and is thus held against further upward movement. The latch sleeve 1165i is now in its lowermost position relative to the mandrel while the latch sleeve 116 moves upwardly thereon as soon as the sensor members 70 move outwardly into the internal latch recess 95 and its latch lugs move out of engagement with the shoulders of the sensor member 70 and into engagement with the inner surfaces 141a thereof. When the shoulders 91 of the sensor members 70 engage the upper nipple shoulder 96, the sensor members are held against upward movement during continued upward movement of the mandrel and of the cross pin 84 until the latch lugs 136 move out of engagement with their inner surfaces 141 whereupon the camming engagement of the shoulders 91 with the shoulder 96 pivots them inwardly so that their shoulders 143 engage the shoulders 142 of the latch bosses. The spring 77 now permit such upward movement of the cross pin 84 relative to the sensor member 70. During the continued upward movement of the signaling device, the sensor members 70 will move in and out 0f their lower positions relative to the mandrel and the latch sleeve 116. The latch lugs 130 will be in the recesses 145 as the signaling device continues its upward movement.

When the shoulders 92a of the sensor members 70a engage the shoulder 96 of such lowermost locating nipple their further upward movement is arrested. The mandrel and the cross pin S4 now move upwardly against the additional force exerted by the springs 110 and 111 thus causing a pressure shock wave to be transmitted through the liquid to the pressure sensing and recording device 168 thus indicating to the operator that the train of tools is at such locating nipple. Upward movement of the mandrel, the cross pin 84 and the latch sleeves relative to the sensor members then moves the latch lugs 130e upwardly and into alignment with the slots 131a of the sensor members 76a whereupon the camming engagement of the shoulders 92a with the upper shoulder 96 of the locating nipple pivots the sensor members 70a inwardly and the camming engagement of their shoulders 135a with the shoulders 134:1 of the latch lugs causes the upper latch sleeve 116:1 to be moved upwardly on the mandrel and the sensor members 70a are then back in the positions illustrated in FIGURE 1. As liquid continues to be pumped into the string of tubing and such string of tools is moved upwardly therethrough, each time the signaling device moves into and through a locating recess a pressure shock wave is transmitted to and sensed by the pressure sensing and recording device 168.

It will now be seen that the signaling device will operate to transmit signals through the liquid which is used to move the train of tools through the tubing whether the signaling device is moving upwardly or downwardly through the string of tubing.

It will now further be seen that the signaling device 20 includes two pairs of sensor members, one pair of which functions when the signaling device is moved in one direction through a flow conductor and the other of which functions when the signaling device is moved in the opposite direction through the flow conductor to increase the force necessary to continue the movement of the signaling device each time the signaling device moves through a section of the ow conductor having an internal recess of predetermined width.

It will further be seen that the signaling device includes latch means for each of the pairs of sensor members for latching them against movement from their expanded or outer positions toward their inner retracted positions and that such latch means is rendered inoperative upon a predetermined movement of the signaling device relative to the expanded sensor members when they are held against movement by an obstruction of the flow conductor to permit the signaling device to move past such obstruction,

The signaling device 200 illustrated in FIGURE 8 is substantially similar to the signaling device 20 differing therefrom in different means for resisting the movement of its cross pins 84- and 84a toward one another and, accordingly, the elements of the signaling device 200 have been provided with the same reference numbers as the corresponding elements of the signaling device 20. The signaling device 200 has instead of the springs 110 and 111 a hydraulic assembly for resisting the movement of the cross pins 84 and 84a. The hydraulic assembly provides a greater force resisting movement of one cross pin toward the other than can the springs 110 and 111 whose size is limited due to the relatively small internal diameter of the mandrel 21. The hydraulic assembly includes a tubular member or cylinder 203 having seal assemblies 204 and 205 closing the upper and lower ends of the cylinder. The upper seal assembly includes a tubular body 206 whose external annular flange 207 provides a downwardly facing shoulder 208 which limits telescoping nward movement of the tubular body into the cylinder. The tubular body is Isecured against displacement from the cylinder by a set screw 209 which extends through a suitable aperture in the cylinder into the threaded bore 210 of the tubular body. The inner conical end portion of the set screw 209 engages an annular seat surface 212 of the tubular body to close a filler port 214 thereof through which liquid may be introduced into the cylinder. The tubular body 206 has an external annular recess in which is disposed an O-ring 215 which seals between the cylinder and the tubular body and with an internal annular recess in which is disposed an O-ring 216 which seals between the closure member and the piston rod 217 of a piston 218.

The seal assembly 205 similarly includes a tubular body 219 which is telescoped in the lower end of the cylinder 203 and secured to the cylinder by a set screw 220 which extends through a suitable aperture of the cylinder into the threaded bore 221 of the tubular body 219. The tubular body is provided with an external annular recess in which is disposed an O-ring 223 which seals between the body and the cylinder and with an internal annular recess in which is disposed an O-ring 224 which seals Ibetween the body and the piston rod.

The piston 218 includes an annular flange 227 integral with the piston rod and having an external annular recess in which is disposed an O-ring 228 which seals between the piston ange and the cylinder. The piston tlange divides the interior of the cylinder into an upper chamber 229 and a lower chamber 230. The piston flange has a vertical flow passage 231 whose lower end opens to a radial slot 232 of tbe piston flange which opens to the lower chamber. The upper end of the vertical ilow passage is closed by a valve ring 234 which abuts the upper annular surface 236 of the piston. The valve ring is biased downwardly against the upper surface of the piston flange to close the upper end of the flow passage by a spring 23S whose lower end engages the upper annular shoulder 239 of the valve ring. The valve ring has internal l.annular flange 240 which extends upwardly into the lower end portion of the spring 238. The top end of the spring engages the downwardly facing shoulder 242 of a spring retainer ring 243. The retainer ring has a downwardly extending annular ange 244 which telescopes into the upper end of the spring. The retainer ring has a downwardly and inwardly sloping internal surface 246 and is held against upward movement on the piston rod by one or more wedge segments 248 whose inner portions are receivable in an external recess 249 of the piston rod and whose outer surfaces engage the internal surface 246 of the retainer ring.

The piston ange also has a second llow passage 252 whose upper end opens to a radial slot 253 which opens to the upper chamber. The lower end of the passage is closed by a valve ring 254 which abuts the bottom surface of the piston iiange and which is biased upwardly towards its closed position by a relatively weak spring 255 whose upper end abuts the bottom surface 257 of the Valve ring. The valve ring is preferably provided with a downwardly extending annular spring retainer ange 25S. The lower end Of spring 255 abuts the spring retainer ring 259 which is similar to the spring retainer ring 243 and is similarly secured to the piston rod by means of wedge segments 260 whose inner portions are received in the annular recess 261 of the piston rod and whose outer upwardly convergent surfaces abut the internal surface of the retainer ring.

It will be apparent that the spring retainer rings may be mounted on the piston rod against longitudinally outward movement thereon by moving them towards the piston flange to positions wherein they permit the wedge segments to be slipped into the recesses and are then moved outwardly on the rod so that the engagement of the conical internal surfaces of the spring retainer rings with the wedge segments then limits their longitudinal outward movement on the piston rod. Any other suitable means may of course be employed to secure the spring retainer rings to the piston rod.

A bypass or metered orifice passage 265 communicates with the lower chamber through the radial slot 232 and with the passage 252 whose upper end communicates with the upper chamber through the radial slot 253.

The piston is biased upwardly by a spring 268 whose opposite ends engage the top surface of the body 219 and the bottom surface of the piston fiange. The upper end of the piston rod engages the bottom surface of the cross pin 84a and the bottom end of the cylinder engages the top surface of the cross pin 84.

The cylinder is filled with an incompressible fluid so that longitudinal movement of the piston rod relative to the cylinder can take place rapidly only when the fluid can iiow from one chamber to the other through one or the other of the flow passages 232 and 252 when its valve ring is in open position. A very slow ow of fluid can take place through the orifice 253 and the passage 252 when the valve rings are in closed positions.

In use, if the signaling device is Abeing pumped downwardly through a string of tubing and the ybosses of the sensor lmembers 70 move outwardly into the recess of the locating nipple and their downward movement is then stopped by the engagement of the bosses with the lower shoulder 97 of such locating recess, movement of the cross pin 84 is arrested in the manner described in connection with the signaling device 20. Continued downward movement of the lmandrel 21 and the cross pin 84a can then be achieved only if the piston 218 moves downwardly relative to the cylinder. Such downward movement of the piston rod is resisted by the pressure of the totally enclosed liuid in the lower portion 230 of the cylinder. This fiuid, to pass to the upper portion 229, must rise in pressure sufiiciently to lift valve ring 234 .away from the piston face 236 and iiow through passage 231. This pressure, in turn, is governed by the thrust of spring 238 and the combined areas of two similar ports 231. It is also affected by the rate of movement of the tool string in the tubing controlled by the pumping rate because iiuid also liows from the lower to the upper portion of the cylinder through the small fixed orifice 265. At normal and at high pumping rates, the effect of orifice 26S is insignificant lbut at low rates, it reduces the pressure required to move the piston relative to the cylinder. In this way, control of the pumping rate becomes a means of controlling the amount of resistance to continued movement of the tool string after being temporarily arrested in the recess of the tubing nipple 99. Variation of the thrust of spring 238 also affects the functioning directly. Once the mandrel 21, the cross pin 84a and the latch sleeves on the mandrel have moved downwardly a sufficient distance relative to the sensor members `and the cross pin 84 to the position wherein the latch sleeves again permits inward movement of the sensor members, the spring 268 moves the cylinder downwardly relative to the piston, the relatively weak spring 255 permitting the valve ring 254 to move downwardly to open position to permit the flow of the hydraulic liquid through the passage 252 into the lower chamber to permit such downward `movement of the cylinder. Downward movement of the cylinder moves the cross pin S4 and the sensor members 70 downwardly relative to the mandrel to their original positions.

If the signaling device is being moved upwardly through the string of tubing and the bosses of the sensor members move outwardly into the recess of a locating nipple, the engagement of the bosses of the sensor members 70a with the upper shoulder nipple then prevent the upward movement of the sensor members 70a and the cross pin Sila. The latch sleeve 116:1 then prevents pivotal inward movement of the sensor members 70a and further upward movement of the cross pin 84a is arrested. Sufficient pressure must then be developed in the liquid 4being pumped upwardly through the tubing to cause the mandrel, the cross pin 84 and the latch sleeves to move upwardly relative to the cross pin 84a. This movement can be accomplished only by a displacement of fluid from the lower portion 230 of the cylinder to the upper portion 229 under exactly the same conditions as before described with respect to downward movement of the tool string.

It will thus be apparent that the hydraulic assembly functions in the same manner whether the signaling device is being moved upwardly or downwardly to resist the movement of one pin relative to the other and that since substantially the full force of the spring 238 is exerted through the valve ring across the relatively small area of the passage 231 to resist flow of the iuid therethrough, the increase in the pressure of the liquid moving the signaling device necessari,1 to release the signaling device for continued movement may be made very great.

Referring now particularly to FIGURES 9 through 14 of the drawings, the signaling device 300 includes a central tubular mandrel 301 having a ball connector 302 secured to one end thereof and a socket connector 303 secured to the other end. The ball connector has an inner threaded portion or pin 305 threaded in the lower end portion of the tubular mandrel, an external flange 306 which provides an upwardly facing annular shoulder 307 which limits inward movement of the ball connector relative to the mandrel, a neck portion 308 and a ball 309.

The socket connector 303 has a first section 310 threaded on the upper end of the mandrel and having an internal annular liange 312 which provides a spherical scat surface 313 inwardly of the passage 315 of the liange. A spherical seat ring 316 is positioned between the upper annular end shoulder 317 of the mandrel and the down- Wardly facing internal annular shoulder 318 of the first section 310, The seat section has a spherical seat surface 319 spaced from and facing the seat surface 313 so that the ball of the ball connector may be positioned for limited universal rotation therebetween. The neclt of such ball connector would of course then extend upwardly and outwardly through the passage 315 of the socket section. The seat ring may be provided with the annular downwardly extending ange 320 which telescopes into the upper end portion of the mandrel.

A protector sleeve 322 is disposed about the mandrel and has an internal annular ange 323 at its lower end which is receivable between the shoulder 307 of the flange 306 of the ball connector and the downwardly facing shoulders 325 of the mandrel. A closure ring 327 substantially closes the space between the mandrel and the upper end of the protector sleeve. The closure ring has a downwardly facing annular recess 328 in which is telescoped the inner upwardly facing flange or reduced portion 329 of the protector sleeve. The sleeve has a pair of longitudinal slots 332 and 333 which extend from the top of the sleeve.

A pair of sensor members 336 have external bosses 338 at their upper ends which are movable outwardly through the slots 333. The sensor members are provided with lower slots 340 whose bottom ends are defined by the upwardly and inwardly convergent surfaces 341 and 342 of the sensor members which provide the pivot edges 343. The pivot edges of the sensor members are received in the downwardly facing recesses 346 of a cross piece 347 which extends through opposed longitudinal slots 348 of the mandrel and into the slots 340 of the sensor members. The upper end portions of the sensor members are biased outwardly toward expanded position by springs 349 whose lower end portions are received in the radially upwardly opening bores 350 and whose upper end portions extend about the Shanks of the pivot pins 352 and engage the annular shoulders 354 of the conical heads 355 of the pins. The upper ends of the pivot pins are received in recesses 357 of the sensor members immediately above their slots 340.

The bosses 338 of the sensor members have upper and lower inwardly convergent cam shoulders 360 and 361, respectively. The sensor members below the lower cam shoulders and above their slots 340 have slots 364 whose upper ends are defined by the downwardly facing shoulders 365, The sensor members have internal recesses 368 and upwardly facing downwardly and inwardly extending shoulders 369 and internal shoulders 370.

A tubular latch sleeve 372 is longitudinally movably mounted on the mandrel and has oppositely facing bosses 373 which project outwardly into the slots 364 of the sensor members when the latch sleeve is in the lower position on the mandrel illustrated in FIGURES 9 and l() of the drawings with the top shoulders 374 of the latch lugs engaging the shoulders 365 of the sensor members. When the latch sleeve is in its upper position on the mandrel, illustrated in FIGURE 11, the outer surfaces 375 of the latch lugs engage the internal shoulders 370 of the sensor members to hold the sensor members in their expanded positions. The upward movement of the latch sleeve on the mandrel is limited by the engagement of its internal upwardly facing shoulders 376 with the downwardly facing annular shoulder 377 of the mandrel. When the mandrel and the latch sleeve are moved upwardly relative to the sensor members from the positions illustrated in FIGURE ll to positions wherein the internal recesses 368 move into alignment with the latch lugs 373, the sensor members may then again move inwardly toward their retracted positions, the latch lugs then being received in the internal recesses of the sensor members with the upwardly and outwardly extending lower shoulders 378 of the lugs engaging the shoulders 369 of the latch lugs of the sensor members.

The latch sleeve is biased toward its upper position on the mandrel by a pair of springs 380 whose inner portions are received in the longitudinal external recesses 381 of the mandrel and in the longitudinal slots 382 of the latch sleeves. The upper ends of the springs bear against the downwardly facing shoulders 383 of the latch sleeve defining the upper ends of the slots and their lower ends bear against the top surfaces 385 ofthe spring support blocks 356 which project outwardly from the mandrel through the slots. The inner circular portions 387 of the blocks are received in suitable lateral apertures 388 of the mandrel and are held in place by the protector sleeve 322. Guide pins 390 extend through the springs 330.

The cross pin 347 is biased downwardly in the mandrel toward its lowermost position illustrated in FIGURES 9 and l0, wherein its further downward movement is arrested by the engagement of its bottom surface with the top surface of the pins 305 and the surface of the mandrel defining the lower ends of its slots 348, by a spring 392 whose upper end bears aaginst the seat section 316 of the socket connector 303 and whose lower end bears against the annular upwardly facing shoulder 394 of the cross pin. The cross pin may have an upward spring retainer portion 395 which telescopes into the lower end of the spring.

In use, the signaling device 300 is connected in a train of well tools, such as the train of tools illustrated in FIGURE 7, in place of the tool signaling device 20, which is to be pumped downwardly through a tubing string provided with the locating nipples 99. The signaling device 300 is connected to such train of tools by its connectors 302 and 303. The sensor members 336 are initially positioned in their retracted or inner positions illustrated in FIGURES 9 and l0 when inserted into the string of tubing. When the train of well tools passes through the uppermost locating nipple 99 connected in the string of tubing and the bosses 333 of the sensor members 336 move into alignment with the latching recess 95 of the uppermost locating nipple, the sensor members are pivoted outwardly and their bosses move outwardly into the latching recess. This pivotal outward movement of the sensor members moves their shoulders 365 out of engagement with the top shoulders 374 of the latch lugs of the latch sleeve. The latch sleeve is thus freed for upward movement on the mandrel and the springs 380 move the latch sleeve upwardly on the mandrel to the position illustrated in FIGURE 1l wherein the outer shoulders or surfaces 375 of the latch lugs engage the shoulders 370 of the sensor members and thus prevent inward movement of the latch lugs. At this time the upward movement of the latch sleeve on the mandrel is limited by the engagement of its upwardly facing internal shoulders 376 with the downwardly facing annular shoulder 377 of the mandrel.

As the downward movement of the train of well tools continues, the bottom cam shoulders 361 of the sensor members engage the lower upwardly facing shoulder 97 of the locating nipple which then prevents further downward movement of the sensor members and of the cross piece since the sensor member cannot pivot inwardly. Further downward movement of the train of well tools can then be accomplished only by a suicient increase in the pressure of the liquid which is moving the train of well tools downwardly to overcome the additional force exerted 'by the spring 392 and move the mandrel and the latch sleeve downwardly relative to the cross piece and the sensor members. The pressure or shock wave generated in the liquid when the downward movement of the sensor members is arrested is sensed and recorded by a suitable device in the manner described in connection with the signaling device 20'. The mandrel and the latch sleeve move downwardly relative to the sensor members and the cross piece until the shoulders 375 of the latch sleeve are moved out of engagement with the shoulders 370 of the sensor members whereupon the camming engagement of the lower cam shoulders 361 of the bosses of the sensor members with the lower shoulder 97 of the locating recess pivots the sensor members inwardly and the shoulders 365 of the sensor members again move into engagement with the top shoulders 374 of the sensor members. The force of the spring 392 is then effective to move the cross piece 347, the sensor members and the latch sleeve downwardly on the mandrel back to their lower positions illustrated in FGURES 9 and 10. This sequence of operation of the signaling device 300 occurs each time the signaling device passes downwardly through a locating nipple 99 of the tubing string.

Upward movement of the train of well tools having the signaling device 300 will not result in the production or generation of such pressure and shock waves in the liquid :being pumped into the string of tubing below such train of well tools to move it upwardly. When the signaling device moves upwardly into the lirst locating recess it reaches during the upward movement of the train of well tools its sensor members will pivot outwardly when their bosses move into alignment with the recess and the latch sleeve will be moved upwardly by the springs 380 to the positions illustrated in FIGURE l1. As the upward movement of the train of well tools continues the upper cam shoulders 360 of the sensor members engage the upper shoulder 96 of the locating nipple and thus their upward movement is arrested. The upward movement of the mandrel, the cross pin and the latch sleeve, however, will continue against the resistance of the springs 349 which bias the sensor members outwardly and upwardly. The latch sleeve will move upwardly with the mandrel since it is biased to its upper position by its springs 380. When the latch lug shoulders 375 move out of engagement with the shoulders 370 of the sensor members, the camming engagement of the cam shoulders 360 with the nipple shoulder 96 pivots the sensor members inwardly and their shoulders 369 are moved into engagement with the lower shoulders 378 of the latch lugs 373, the outermost portions of the latch lugs being received in the internal recesses 36S of the sensor members. The sensor members will then remain in this lower position relative to the latch sleeve and the latch sleeve will then remain in its upper position on the mandrel during the continued upward movement of the string of well tools through the string of tubing. Since the springs 349 are relatively weak no appreciable increase in pressure of the pumped liquid is required to cause upward movement of the signaling device through the locating nipples.

It will be apparent that the signaling device 300, when connected in a train of well tools and moved through a string of tubing provided with the locating nipples with its ball connector 302 in its lowermost position, will generate or produce the shock and pressure waves in the liquid moving the train of well tools downwardly through such string of tubing. lf it is desired that the location of the train of well tools be precisely known both during its downward and upward movement through the string of tubing, the train of well tools would be provided with two of the signaling devices 300, one of them being connected in the train of tools in the position illustrated in FIGURES 9 and l0, the other being connected in the string of well tools in vertically reversed position by suitable connecting means so that one such signaling device would produce pressure and shock waves during downward movement of the train of tools through the ow conductor and the other would produce the pressure and shock waves in the liquid during its upward movement of the train of tools through the string of tubing.

It will now be seen that each of the described and illustrated forms of the signaling device embodying the invention includes a mandrel having a pair of sensor members mounted for limited longitudinal movement thereon and for laterally outward movement relative thereto, a latc'h sleeve movably mounted on the mandrel and biased for movement to its latching position wherein the latch sleeve holds the sensor members, when they move to their expanded position, against movement to their retracted positions, and means for resisting movement of the mandrel and the latch sleeve relative to the sensor members, when the sensor members are in their extended positions and held against movement, in the low conductor, as by their engagement with an internal annular shoulder of a ow conductor, to positions wherein the latch is out of latching engagement with the expanded sensor members.

It will further be seen that the sensor members are biased toward positions where they will be engaged by the latch sleeve when it moves to its latching position in the well tools and 200 by the spring 77 and in the v/ell tool 300 by the similar springs 349 which bias the sensor members laterally outwardly.

Referring now particularly to FIGURES l5 through 27 of the drawing, the signaling device 400 embodying the invention includes a tubular main body or mandrel 401 and sensor and control assemblies 402 and 403, respectively, mounted on the mandrel. A top socket connector assembly 405 is rigidly secured to the upper end of the mandrel. The socket connector assembly has an internal annular ange 406 into which is threaded the upper end portion of the mandrel and an internal annular llange 407 which provides an annular arcuate seat surface 408 which is spaced above the similar seat surface 409 of a seat ring 410 threaded in the ange 406 above the top end of the mandrel. The ball of a ball connector assembly, such as the ball 411 of a ball connector assembly 412 shown mounted on the lower end of the mandrel, may be positioned for limited universal rotation. A spring retainer nut 413 is threaded in the upper end of the Inandrel for reasons to be described below. The top connector member and spring retainer nut are held against rotation relative to the mandrel and each other by a pin 413a which extends through aligned apertures thereof.

The ball connector assembly 412 is mounted on the lower end of the main mandrel by means of a screw 414 whose head provides an annular top shoulder 414 which engages the downwardly facing shoulder 415 of the upper internal annular liange 416 of the upper section 417 of the -ball connector assembly. The lower section 418 of the ball connector assembly is threaded on the upper section and has a dependent neck 419 with which the ball 411 is integral. The signaling device may be connected in a train of tools by similar connector assemblies. For example, a lower well tool of a train of tools is connectable to the bottom connector assembly, and thus to the mandrel, by a socket connector assembly on the upper end of the lower well tool which receives the ball 411 of the signaling device and an upper well tool is connectable to the top connector assembly by a ball connector assembly on the lower end of the upper tool whose ball is positioned between the seat surfaces 408 and 409 of the top connector assembly.

The sensor assembly 402 includes a substantially tubular cage 425 longitudinally slidable on an intermediate portion of the mandrel and a pair of sensor members 428 and 428a pivotally mounted on the cage. The cage includes a pair of upper and lower tlange portions 432 and 433, spaced vertical side portions 434 and 435, and horizontal planar brace portions 436 and 437 which extend between the side portions. The cage may be machined from a single piece of work stock so that its various portions are integral with one another, or, if desired for ease of manufacture, the vertical side portion 435 and the brace portions may be formed of separate pieces which may be welded to the other portions of the cage as illustrated in FIGURE 22. The cage has been shown in views other than FIGURE 22 as being formed of a single piece for clarity of illustration. The vertical side portion `434 has a horizontal outwardly extending ange portion 438. The top flange member 432 and the flange portion 438 are provided with pairs of aligned apertures 444 and 445, respectively, which are aligned with one another and with a pair of upwardly opening bores 446 in the bottom tlange portion 433. Pivot pins or posts 448 and 448a extend through the apertures 444 and 445 and into the bores 446 and are rigidly secured by pins 451 which extend through suitable aligned apertures in the upper ends of the pins and in the upper flange portion 432. The sensor member 428 has horizontal top and bottom arms 461 and 462 which are positioned between the upper and lower flange portions 432 and 433 of the cage and arms 463 and 464 which are positioned above and below the middle flange portion 438 of the cage. The arms of the sensor member 428 are provided with vertical apertures 465 which are aligned with the apertures of the flange portions of the cage and through which the pivot pin 448 extends whereby the sensor member 428 is pivotally movable about the vertical axis of the pin. The sensor member 428 is biased in a counterclockwise direction, FIG- URE 18, by a pair of springs 467 and 468 disposed about the pin, the spring 467 being disposed between the arms 461 and 463 and the spring 468 being disposed between the arms 464 and 462. The lower end portion of the spring 467 is secured to the sensor member as by insertion into a bore thereof and its upper end portion engages one edge of the vertical frarne portion 434. The lower spring 468 has its lower end portion similarly secured to the sensor member and its upper end portion engages the opposite edge of the portion 434. The springs 467 and 468 are prestressed during the installation of the sensor member 428 on the cage 425 and thus bias the sensor member 428 outwardly in a counter-clockwise direction, FIGURE 18. The lateral outward pivotal movement of the sensor members is limited by the engagement of the inner surfaces of their arms with the vertical portion 434 ofthe mandrel.

The sensor member 428a is of similar structure to the sensor member 428 and similarly mounted on the cage and biased outwardly in a clockwise direction about the axis of tne pin 448a, as seen in FIGURE lS, and, accordingly, elements of the sensor member 428s and its mounting and biasing means have been provided with the same reference numerals, to which the subscript a 

